Privacy was top of the agenda for Google when it held the group's first European media day in Paris this week.

Google recently agreed to EU directives which means it has agreed to anonymise the data it holds on searches after 12 to 18 months.

However, Marissa Mayer, vice-president of search, said the web giant would look at letting users opt to have their search data held longer. She said the more information the company had, the better it could predict the intent of the surfer and return results that were more personalised for that individual search.

Google's biggest problem is trying to comprehend what a user is actually searching for as there is often a disparity between what the user types into the search engine and what they want.

Google claimed it searches tens of billions of pages. According to Mayer, the number of pages it searches has grown by more than a factor of a 1,000 since 1998.

"We have continually tried to improve our speed, and it has yielded more and more searches. Our goal is to have a Google search as fast as the speed of light to and from our data centres from the user's location."

The internet company is also focusing on environmental issues, and said it was investing in renewable energy sources and offsetting emissions that could not be eliminated directly in order to go carbon-neutral.

Urs Hoelzle, Google's operations senior vice-president, said the company did not want to be just carbon-neutral but agitators for change.

"Hopefully, we will have a positive impact on the larger environment. We want to first take care of our own energy efficiency and renewable energy, but also to reach to the world as a whole."

Google chief executive Eric Schmidt reiterated some of Mayer's comments about search, saying the company was trying to close the gap in what was typed and what was meant.

He also said one of the main focuses for the company would be to work with more content providers, such as the BBC, in addition to digitising more libraries of books.

He mentioned the Alexander Library in Egypt as an example of a project where many of the books had never been translated, something he would like to get Google involved with.

Other future challenges include having Google ubiquitous on mobile devices such as phones and PDAs.

The company is also working towards users being able to store, for example, all their PC's hard disk content on Google as a back-up in case their computer fails.

"One of the things we think about is what the next billion people going on to the internet will do. And how do we get people online even in the poorest parts of the world? We are determined to get those people online in the next few years."

When asked if Google's application such as its word processor and spreadsheet programme were the start of an attempt to go head-to head with Microsoft in the application space, Schmidt said he kept telling people the company was not doing that, but no one believed him.

"The answer is no. If you look at Google apps, they really are very different from the traditional Microsoft applications.

"The easiest way to judge this is to use them, then you can decide what they're good for and what they're not. We don't position them as competitive."